net/fpc-pcap: Remove redundant pcap option
The default LIBPCAP option didn't do anything. It set a LIB_DEPENDS
that is always satisfied by the base libpcap so no dependencies were
registered.
While here, set PORTREVISION. The slave ports of fpc should have have
PORTREVISION?= line, even if the value is zero. This one didn't, so
we have to bump to 2 because the master port already had set it to 1.

FPC ecosystem: Upgrade version 2.6.4 => 3.0.0
This is the first major release of FreePascal in nearly four years.
There are a ton of new features, way more to list here. see:
http://wiki.freepascal.org/FPC_New_Features_3.0
Several new unit ports were added, some were contracted. Most of
those were absorbed into the main FPC packages, but two units are
no longer supported: sndfile and matroshka.
All 99 remaining ports (including Lazarus ports) were build tested
on FreeBSD i386 and amd64 Release 10.2